Electric liquid heater



B. W. MACY ELECTRIC LIQUID HEATER 2 Sheets-Sheet 1 ATTORNEY Sept. 24, 1929.

Filed June 1928 wagwg wwxwz V Sept. 24, 1929. w, cY 1,729,587

ELECTRIC LIQUID HEATER 2 Sheets-Sheet 2 Filed June 4, 1928 .11.. IIIIIIIIIIIH ImlH INVENTOR Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE ELECTRIC LIQUID HEATER Application filed June 4,

This invention relates to improvements in electric liquid heaters, and it consists of the constructions, combinations and arrangements herein described and claimed.

An object of the invention is to provide an apparatus for heating water or other liquids electrically, one of the purposes being to so arrange the bottom terminals that short circuiting by virtue of an accumulation of sediment will not occur under ordinary circumstances, and cannot occur unless such accumulation becomes excessive.

Other objects and advantages appear in the following specification, reference being had to the accompanying drawings in which,

Figure 1 is a perspective View of the improved electric liquid heater,

Figure 2 is a central vertical section, the switch being shown in elevation,

Figure 3 is a cross section taken on the line 33 of Figure 2,

Figure 4: is a detail enlarged section, particularly showing one of the protected terminals,

Figure 5 is a detail perspective view of the top insulating bar,

Figure 6 is a vertical section of the heater, illustrating a slightly modified construction,

Figure 7 is a cross section taken on the line 77 of Figure 6,

Figure 8 is a cross section taken on the line 88 of Figure 6,

Figure 9 is a detail vertical section taken on the line 99 of Figure 6, the wires being omitted.

It has long been an object to produce a water heating apparatus that will not only be ready for action at all times, especially when the need for hot water is most urgent, but also one that will be reasonably simple in its construction so that the cost of manufacture and installation may place the heater within the financial reach of a larger number of persons who should enjoy the convenience to be afforded. While a number of types of heaters are known and are in use, it is to be conceded that an electrically operated heater has outstanding points of advantage if nothing more than compactness and cleanliness.

1928. Serial No. 282,529.

The electrical heater herein disclosed is of the direct immersion type, that is to say, the resistance elements are immersed in the liquid to be heated. The resistance elements are actually suspended in the liquid so that the latter will have access to all parts of the element with the obvious advantage that a quicker and more thorough heating effect will result.

There is another purpose in the particular construction disclosed. Both forms of the invention employ what is known as a top insulating bar to which the upper ends of the resistance elements are anchored. This part operates as a battle, causing the hot stream of water to be diverted in the outward direction and against the inner wall of the heater barrel, forming a solid cushion of hot water which prevents the outer column of cold water from passing out into the receiving tank or into the outlet.

All this will presently be made plain, and reference is made to the drawin s. The heater barrel 1 has an outlet 2 at the top, and a bottom flange 3 which is bolted at 4 to the flange 5 of a switch coupling 6. This coupling carries a conventional snap switch 7 and contains the wires 8 of an electrical circuit. A boss 9 (Figs. 1, 3 and 7) provides a liquid inlet. The boss is cast upon the flange 3 at one side of the barrel.

Electrical resistance elements are so suspended within the barrel 1 that access to all parts thereof may be had by the liquid within the barrel. The elements, in the present instance. are composed of coils 10 of wire of some suitable resistance material. In the form shown in Figure 2 there are two coils 10, connected in series at the upper ends at 11, and anchored at the lower ends to the terminal screws as at 12 and In the form shown in Figures 6 and 9 the coils 10 are four in number but the same connections and modes of anchorage are employed.

A stud l4, threaded at both ends, is screwed into the flange plate 5 at its lower end and receives a lock nut 15 at its upper end. nut locks the assembly which comprises a porcelain spacer sleeve 16 and a top insulating bar 17. The sleeve receives the stud 1 1 This and acts as a rest for the top bar. The sleeve also has a bead 18 near the bottom which bead, however, is utilized only in the form of the invention in Figures 6 to 9.

The top insulating bar 17 has pairs or": holes 19 (Fig. through which the upper ends of the elements 10 are loooed or threaded to produce the top anchorage. The free ends of the elements are then twisted together. The bottom terminals include porcelain bushings 20 and mica washers 21 on the upper side of the plate 5, and mica washers 22, brass washers 23, nuts 2% and connectors 25 on the lower side of the plate 5. The porcelain bushings are of suitable height, thus locat ing the points of connection of the elements 10 with the terminal screws 12 and 13 suliiciently high above the bottom of the heater barrel to permit an accumulation of sediment over a long period before the danger of short circuiting through the sediment will become imminent. In this respect the bottom of the heater barrel may be said to constitute a sediment well or trap.

Reference is now made to Figures 6 to 9. In its major respects the modification is identical with the form in Figures 1 to a: as is evidenced by the reference characters 01* corresponding parts. The dilii'erences reside in the electrical resistance elements and in the mode of suspending them.

Use is now made or" the head 18 on the spacer sleeve 16 to support a bottom insulating bar 26 which is similar in configuration to the top insulating bar 17. But in view or the fact that four coils 10 are now used, in place of two as in Figure 2, the insulating bars are made in the form of crosses so that the bottom loop 27' and top loops 28 may be accommodated more readily.

It is to be observed in both forms of the invention that it would be an easy matter to take the heater apart for any particular purpose. The coupling 6 constitutes a founda tion upon which all parts of the heater are mounted, those parts being the switch 7, the resistance elements and the appurtenances thereof, and the heater barrel 1. The latter is inverted upon the resistance elements like a hood, and should it become necessary to gain access to the interior, it would only be necessary to remove the bolts t and pull the coupling 6 away from the barrel. Tie latter would remain connected in the pipe line.

The operation is readily understood. It is obvious that water or other liquid will enter at the inlet 9 and pass out at the outlet 2. The elements 10 will heat the water, the current presumably having been turned on, so that a hot stream will flow at the outlet. It has been made plain that the bushings 20 place the connections to the resistance elements sutiiciently high above the flange plates 5 to convert the space between the top of.

the bushings and the bottom of the heater barrel into a sediment trap.

The top insulating bars perform an important function in addition to supporting the upper ends of the resistance elements. They act as ballle plates, tending to divert the hot lip-flowing stream of water, causing some of the water to reach the inner walls ot the barrel 1 and form a solid cushion of hot water w rich prevents an outer column of cold water from passing out of he outlet 2.

lVhile the construction and arrangement of the improved liquid heater is that of a generally preferred form, obviously modifications and changes may be made without departing from the spirit of the invention or the scope of the claims.

I claim 1. A liquid heater comprising a barrel, a resistance element spaced within the barrel, and a bar to which one end of the element is attached and from which the element is suspended in a liquid in the barrel, acting as a battle plate to divert the hot stream of fluid from the element and form a cushion of hot fluid adjacent to the inner wall of the barrel.

A heater comprisin a barrel, a resist-- ance element, a sleeve along which the element extends, and an insulating bar resting upon and sin-mounting the sleeve, to which bar the element is attached, said bar acting as a balile plate within the barrel.

3. A heater comprising a barrel, a plate providing a bottom for the barrel, resistance elements, terminal screws insulated from and carried by the plate to which screws the terminal ends of the elements are connected, an insulating sleeve along which the elements extend, an insulating bar sin-mounting the sleeve, at which bar the other ends of the elements are connected, a nut by which the parts are locked, and a stud passing through the bar and sleeve, being threaded at both ends respectively to screw into the bottom plate and receive the nut.

a. A liquid heater con'iprising a barrel with an open end, a plate sccurable over the open end to close the barrel, resistance elements, means by which they are supported upon the plate, terminal screws to which the ends of the elements are connected, and means to insulate the screws from the plate, said means including porcelain bushings extending up from the bottom of the plate and locking the point of connection of the elements with the screws well above the bottom, to provide a sediment trap.

5. A heating unit comprising a plate, a resistance element comprising a coil of wire, a single insulating sleeve having a bead adjacent to the plate, and a pair of insulating bars between which the element extends, one surmounting the sleeve and the other slipped upon the sleeve until supported by the bead.

6. A heater comprising a mounting plate,

a heating unit comprising a resistance element consisting of a coil of Wire having terminals extending frqm the plate, a pair of insulating bars between which the element extends, each acting as a bafiie plate to divert the hot stream of fluid from the element, insulating means by which the bars are spaced, and a tube attached to said plate, encasing said heating unit, being open at one end and having an opening adjoining said plate.

BARNETT W. MACY. 

